Active comfort controlled bedding systems

ABSTRACT

Active comfort controlled bedding systems and processes of operating the bedding systems generally include a variable firmness control. The active comfort controlled bedding system can include a control unit in electrical communication with a signal generating layer configured to generate heat and alter a firmness property of at least one viscoelastic foam layer, wherein the amount of heat is based on a decrease of the glass transition temperature as a function of the percentage of humidity in the environment. In other embodiments, the bedding system is provided with at least one foam layer comprising a phase change material stratified in a foam structure of the at least one foam layer; and the at least one foam layer is heated to a temperature greater than a melt temperature of the paraffin wax to soften the at least one foam layer. In other embodiments, ambient humidity conditions can be changed.

BACKGROUND

The present disclosure generally relates to active comfort controlledbedding systems. More particularly, the present invention relates toactive comfort controlled bedding systems including a mattress coreincluding at least one foam layer having variable firmness properties inresponse to a signal.

Varieties of mattress constructions are well known and are generallysupplied in different degrees of firmness. For example, some mattressesare extremely soft and yieldable, i.e., plush, while others arerelatively rigid and unyielding, i.e., firm. Once a mattress of aparticular firmness has been purchased, it cannot generally be changedwithout the necessity of having to purchase another mattress. Individualpreferences desired by one or two people sleeping on one mattresssurface for comfort or to address pain or life changing events is oftennot fulfilled by current mattress designs.

The problem of supplying mattresses with various degrees of firmness isa considerable one. This applies to manufacturers and retailers who aretypically required to maintain a large inventory of mattresses withdifferent degrees of firmness. In addition, considerable difficultyarises with respect to hotels and the like, which are often required tosatisfy the particular requirements or tastes of its guests as to thefirmness of the mattress in a particular room. For these reasons, it isdesirable to provide a single mattress, which easily adjusts to providedifferent degrees of firmness.

Typical foam layers used by conventional bedding manufacturers inmattresses have attempted to compensate for the infinite combination ofconsumer preferences by releasing several models of firmness for eachbedding line, wherein the foam layers are selected to have a uniform andstatic firmness level. With regard to the use of foam layers used inmattresses, these materials are typically specified to have a glasstransition temperature (Tg) below 72° F. with no regard to humiditylevels. In some instances, the foam layers have a glass transition lowerthan 72° F. to account for end users' preference to keep the bedroomcooler during use.

BRIEF SUMMARY

Disclosed herein are active comfort controlled bedding systems. In oneor more embodiments, the active comfort controlled bedding systemincludes at least one viscoelastic foam layer having a glass transitiontemperature greater than 60° F. at 0% humidity, wherein the activecomfort controlled bedding system is in an environment having greaterthan 0% humidity; a signal generating layer underlying the at least oneviscoelastic foam, the signal generating layer comprising athermoelectric fabric, a heat transfer device, or a resistive heatingelement; and a control unit in electrical communication with the signalgenerating layer configured to generate heat and alter a firmnessproperty of the at least one viscoelastic foam layer, wherein the amountof heat is based on a decrease of the glass transition temperature as afunction of the percentage of humidity in the environment.

In one or more embodiments, the active comfort controlled bedding systemincludes at least one foam layer comprising a phase change materialstratified in a foam structure of the at least one foam layer; a signalgenerating layer underlying the at least one foam layer, the signalgenerating layer comprising a thermoelectric fabric, a heat transferdevice, or a resistive heating element; and a control unit in electricalcommunication with the signal generating layer effective to heat thephase change material above a melting temperature thereof and alter afirmness property of the at least one foam layer.

In one or more embodiments, a process for changing a firmness propertyof a viscoelastic foam layer in a mattress assembly includes providingthe mattress assembly with at least one foam layer comprising a phasechange material stratified in a foam structure of the at least one foamlayer; and heating the at least one foam layer to a temperature greaterthan a melt temperature of the phase change material to soften the atleast one foam layer.

In one or more embodiments, the process for changing a firmness propertyof a viscoelastic foam layer in a mattress assembly includes providingthe mattress assembly with at least one viscoelastic foam layer having afirst glass transition temperature greater than 60° F. at 0% humidity,and a second glass transition temperature different than the first glasstransition temperature at a % humidity greater than 0, and whereinheating the viscoelastic foam layer comprises heating above the secondglass transition temperature to alter the firmness property.

In one or more embodiments, a process for changing a firmness propertyof a foam layer in a mattress assembly includes providing the mattressassembly with at least one viscoelastic foam layer having a first glasstransition temperature greater than 60° F. at 0% humidity, and a secondglass transition temperature less than the first glass transitiontemperature at a % humidity greater than 0, and heating the at least oneviscoelastic foam layer and/or changing ambient humidity conditionsabout the at least one viscoelastic foam layer to alter the firmnessproperty.

The disclosure may be understood more readily by reference to thefollowing detailed description of the various features of the disclosureand the examples included therein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Referring now to the figures wherein the like elements are numberedalike:

FIG. 1 graphically illustrates glass transition temperature shift of apolymeric foam as a function of relative humidity in accordance with oneor more embodiments;

FIG. 2 graphically illustrates the glass transition temperature, storagemodulus, and loss modulus shift of a polymeric foam as a function oftemperature in accordance with one or more embodiments;

FIG. 3 is a partial perspective cut away view of a mattress including anactive comfort layer in accordance with one or more embodiments;

FIG. 4 is a side perspective view of an expanded thermoelectricapparatus that can integrated into a flexible fabric in accordance withone or more embodiments;

FIG. 5 is an exemplary flexible thermoelectric fabric in accordance withone or more embodiments;

FIG. 6 is a perspective cut-away view of an exemplary mattress assemblythat includes a flexible thermoelectric fabric in accordance with one ormore embodiments;

FIG. 7 is a top down view of an exemplary signal generating layerincluding resistive heating elements in accordance with one or moreembodiments; and

FIG. 8 is an exemplary signal generating layer including a fluid basedheat transfer device in accordance with one or more embodiments.

DETAILED DESCRIPTION

Disclosed herein are active comfort controlled bedding systems. As willbe discussed in greater detail below, the active comfort bedding systemsgenerally include a mattress core material that is reactive to signalsto provide personalized comfort. More particularly, the mattress corematerial includes a polymeric foam layer that has a variable firmnessproperty in response to a thermal signal, i.e., the polymeric foam layercan be made to selectively stiffen or soften in response to a thermalsignal sent to a specific zone.

Viscoelastic polymeric foam materials for use in mattresses aretypically specified to have a glass transition temperature at or below72° F. with the intent that the layer is not overly firm when firstexperienced by an end user. However, this specification is provided at ahumidity level of 0%, i.e., a level that does not occur in actualpractice. In actuality, when considering the relative humidity of theactual environment in which the mattress is used, the glass transitiontemperature is markedly lower than the glass transition temperaturespecified at 0% humidity depending on the percentage of relativehumidity at the point of use.

As graphically shown in FIG. 1, a reduction of about 30° F. in the glasstransition temperature has been observed for the same viscoelastic foamas a function of increased relative humidity. That is, the sameviscoelastic polymeric foam with a glass transition temperaturespecified at 74° F. and 0% humidity exhibited a glass transitiontemperature at 27% humidity of about 44° F. Storage modulus and lossmodulus also decreased as a function of increased relative humidity.Consequently, viscoelastic polymeric foams for use in the presentmattress core can be specified with glass transition temperaturesgreater than about 72° F. at 0% humidity in mattress applications giventhe effect that relative humidity has been found to have on the glasstransition temperature. As a result, the firmness property of theviscoelastic polymeric foam having glass transition temperatures greaterthan about 72° F. at 0% humidity can be modulated upon application of athermal signal, which can be controlled by the end user depending onhis/her preferences so as to provide a firmer or softer feel to theviscoelastic polymeric foam layer.

In one or more embodiments, the viscoelastic polymeric foam layer isspecified to have a glass transition temperature at 0% humidity greaterthan about 72° F. In one or more other embodiments, the viscoelasticpolymeric foam is specified to have a glass transition temperature at 0%humidity greater than 80° F., and in still one or more otherembodiments, the viscoelastic polymeric foam is specified to have aglass transition temperature at 0% humidity greater than 90° F. Theincreased glass transition temperature of the viscoelastic polymericfoams for mattress applications allows the end user to adjust thefirmness property of the viscoelastic polymeric foam by application of athermal signal that radiates heat to the viscoelastic polymeric foamlayer in an amount effective to soften the viscoelastic foam. The amounteffective to soften the viscoelastic foam generally depends on therelative humidity level in which the viscoelastic polymeric foam isused, which is depressed relative to the original specification at 0%humidity.

As graphically shown in FIG. 2, the glass transition temperature (Tg) asapplied to viscoelastic polymeric foams is a temperature region in whichthe foam transitions from firm to soft, which is often reported as thepeak of the tan δ curve, which can generally be defined as the lossmodulus (viscous behavior)/storage modulus (solid-like behavior). In theFigure, softening occurs for a particular viscoelastic polymer as thetemperature is increases above about 72° F. As a result, the mattresscore including the viscoelastic polymeric foam can be tailored to an enduser's preferences so as to provide a desired firmness. With theapplication of heat, a firm foam (i.e., one with a high Tg and highhardness) can be softened by forcing it to progress through the phasechange provided by heating the viscoelastic polymer foam to atemperature greater than its glass transition temperature.

FIG. 3 shows an exemplary mattress assembly 100 with a mattress core102, at least one adjustable comfort foam layer 104, and a signalgenerating layer 106. The mattress core 102 can be constructed of avariety of resiliently compressible materials such as an innerspringcoil assemblies, foam layers and combinations thereof. Exemplaryinnerspring coil assemblies include, without limitation, a type referredto as Marshall construction consisting of a plurality of coil springshoused within fabric pockets arranged in a closely packed connectedarray.

The mattress core foam layers are generally fabricated from polymers andgenerally include latex, polyurethane, viscoelastic foam (also referredto as memory foam), or the like. With regard to viscoelastic foams,these foams are a form of polyurethane, although with slightly differentcomponents that changes the viscosity and density to yield the “memory”characteristics. The viscoelastic property of a polymer can be studiedby dynamic mechanical analysis (DMA) where a sinusoidal force (stress σ)is applied to a material and the resulting displacement (strain) ismeasured. For a perfectly elastic solid, the resulting strain and thestress will be perfectly in phase. For a purely viscous fluid, therewill be a 90-degree phase lag of strain with respect to stress.Viscoelastic polymers have the characteristics in between where somephase lag will occur during DMA tests. Varying the composition ofmonomers and cross-linking defining the viscoelastic foam layer can addor change the functionality of a polymer that can alter the resultsobtained from dynamic mechanical analysis.

In one or more embodiments, the adjustable comfort foam layer 104 is aviscoelastic polymeric foam layer, wherein the viscoelastic polymericfoam is specified to have a glass transition temperature at 0% humidityof about 60° F. or greater. In one or more embodiments, the viscoelasticpolymeric foam is specified to have a glass transition temperature at 0%humidity greater than 80° F., and in still one or more otherembodiments, the viscoelastic polymeric foam is specified to have aglass transition temperature at 0% humidity greater than 90° F.

In one or more other embodiments the adjustable comfort foam layer 104is a non-viscoelastic foam or the viscoelastic foam as described above,wherein a phase change material such as encapsulated paraffin waxpellets or other phase change material or combination of phase changematerials can be stratified into the foam structure that would ‘melt’ inresponse to a thermal signal from the signal generating layer, therebymaking the foam/wax composite structure softer.

The adjustable comfort foam layer 104 can be one of many layers definingthe mattress core and is oftentimes surrounded by a quilted fabric orticking, which generally serves as an outer decoration as well as holdsthe parts of the mattress together as one whole mattress. Additionally(not shown), the whole mattress is typically surrounded by a quiltedcover, for added comfort and aesthetics. The bedding systems may be ofany size, including standard sizes such as a twin, full, queen,oversized queen, king, or California king sized mattress, as well ascustom or non-standard sizes constructed to accommodate a particularuser or a particular room. The active comfort controlled bedding systemscan be configured as one sided having defined head, foot and torso(i.e., lumbar) regions.

Suitable foams for the different layers including the adjustable comfortlayer that include foam, include but are not limited to, polyurethanefoams, latex foams including natural, blended and synthetic latex foams;polystyrene foams, polyethylene foams, polypropylene foam,polyether-polyurethane foams, and the like. Likewise, the foam can beselected to be viscoelastic or non-viscoelastic foams. Some viscoelasticmaterials are also temperature-sensitive, thereby also enabling the foamlayer to change hardness/firmness based in part upon the temperature ofthe supported part. Unless otherwise noted, any of these foams may beopen celled or closed cell or a hybrid structure of open cell and closedcell. Likewise, the foams can be reticulated, partially reticulated ornon-reticulated foams. The term reticulation generally refers to removalof cell membranes to create a cell structure that is open to air andmoisture flow. Still further, the foams may be gel-infused, may includeconductive materials, may include phase change materials, or may includeother additives in some embodiments. The different layers can be formedof the same material configured with different properties or differentmaterials.

The various foams suitable for use in the foam layer may be producedaccording to methods known to persons ordinarily skilled in the art. Forexample, polyurethane foams are typically prepared by reacting a polyolwith a polyisocyanate in the presence of a catalyst, a blowing agent,one or more foam stabilizers or surfactants and other foaming aids. Thegas generated during polymerization causes foaming of the reactionmixture to form a cellular or foam structure. Latex foams are typicallymanufactured by the well-known Dunlap or Talalay processes.Manufacturing of the different foams are well within the skill of thosein the art.

The different properties for each layer defining the foam may include,but are not limited to, density, hardness, thickness, support factor,flex fatigue, air flow, glass transition temperature, variouscombinations thereof, and the like. Density is a measurement of the massper unit volume and is commonly expressed in pounds per cubic foot. Byway of example, the density of the each of the foam layers can vary. Insome embodiments, the density decreases from the lower most individuallayer to the uppermost layer. In other embodiments, the densityincreases. In still other embodiments, the density is non-uniformbetween adjacent layers. In still other embodiments, one or more of thefoam layer can have a convoluted surface. The convolution may be formedof one or more individual layers with the foam layer, wherein thedensity is varied from one layer to the next. The hardness properties offoam are referred to as the indentation force deflection (IFD) and ismeasured in accordance with ASTM D-3574. Like the density property, thehardness properties can be varied in a similar manner. Moreover,combinations of properties may be varied for each individual layer. Theindividual layers can also be of the same thickness or may havedifferent thicknesses as may be desired to provide different tactileresponses.

In some embodiments, the adjustable comfort foam layer can be acomponent of the mattress core.

The hardness of the layers generally have an indention force deflection(IFD) of 7 to 22 pounds force for viscoelastic foams and an IFD of 7 to65 pounds force for non-viscoelastic foams. IFD can be measured inaccordance with ASTM D 3574. The density of the layers can generallyrange from about 0.8 to 2.5 pounds per cubic foot for non-viscoelasticfoams and 1.5 to 8 pounds per cubic foot for viscoelastic foams.

The signal generating layer 106 is shown underlying the mattress core102. However, it should be noted that the signal generating layer 106can be singular or plural, and be included anywhere within the mattressassembly including but not limited to the mattress, the mattressfoundation, intermediate the mattress and mattress foundation, orcombinations thereof. The at least one adjustable comfort foam layer 104is typically located at or in close proximity to the support surface.The signal generating layer 106 can include a resistive heating element,a thermoelectric fabric layer, or a heat transfer device and can be incontact with or spaced apart from the adjustable comfort foam layer solong as the adjustable comfort foam layer can be heated in an amountsufficient to change the firmness property. Moreover, the signalgenerating layer 106 can be compartmentalized into different zones tochange the firmness within a particular zone or multiple zones of thefoam layer. Likewise, the signal generating layer 106 can be configuredto provide different zones. A control unit 108 is electronicallyconnected to the heat source and can be programmed to adjust the heat asdesired.

As noted above, the signal generating layer 106 can be a resistiveheating element, a thermoelectric fabric or a heat transfer device.

Flexible thermoelectric fabrics have been developed for use in variousapplications. For example and without limitation, thermoelectric fabricsare disclosed in U.S. Publication No. 2013/0312806, which is titled“Thermoelectric Apparatus and Applications Thereof” and is herebyincorporated by reference in its entirety. These flexible thermoelectricfabrics can employ a layered p-n junction material to generatetemperature gradients from electricity. Modules of the material may bearranged in series, parallel or a combination in order to achieve thedesired temperature distribution. The thermoelectric fabric remainsflexible due to its polymeric construction. This allows for retainedcomfort when placing the layers closer to the surface of the mattresswhere the body is generating heat. Thermoelectric fabrics can also coveran entire sleep surface if needed. This can decrease the positionalrequirements of the sleeper allowing them to move freely in the mattresswhile still experiencing uniform temperature distribution.

Flexible, polymer-based thermoelectric fabrics can be constructedthrough the lamination of doped p- and n-junction polymers, or othermaterials, separated by an insulating material. These laminated modulescan be stacked and arranged in series, parallel or a combination inorder to achieve the desired temperature distribution. Polymer basedthermoelectric fabrics can be placed nearer the surface of a mattress toincrease efficiency of the cooling or heating process.

As is explained in greater detail in U.S. Publication No. 2013/0312806,FIG. 4 illustrates an expanded side view of a thermoelectric apparatusthat forms example flexible thermoelectric fabrics. The thermoelectricapparatus illustrated in FIG. 4 comprises two p-type layers 1 coupled toan n-type layer 2 in an alternating fashion. The alternating coupling ofp-type 1 and n-type 2 layers provides the thermoelectric apparatus az-type configuration having p-n junctions 4 on opposite sides of theapparatus. Insulating layers 3 are disposed between interfaces of thep-type layers 1 and the n-type layer 2 as the p-type 1 and n-type 2layers are in a stacked configuration. As shown, the thermoelectricapparatus provided in FIG. 4 is in an expanded state to facilitateillustration and understanding of the various components of theapparatus. In some aspects, however, the thermoelectric apparatus is notin an expanded state such that the insulating layers 3 are in contactwith a p-type layer 1 and an n-type layer 2.

FIG. 4 additionally illustrates the current flow through thethermoelectric apparatus which is resultant to exposing thethermoelectric apparatus to a temperature differential across bothsides. It is also possible that current flow causes said temperaturedifferential. Electrical contacts X are provided to the thermoelectricapparatus for application of the thermally generated current to anexternal load or to cause the temperature differential due to a currentfrom an external power source.

Again, as is explained in greater detail in U.S. Publication No.2013/0312806, FIG. 5 illustrates an exemplary thermoelectric apparatus200, wherein the p-type layers 201 and the n-type layers 202 are in astacked configuration. The p-type layers 201 and the n-type layers 202can be separated by insulating layers 207 in the stacked configuration.The thermoelectric apparatus 200 can be connected to an external load byelectrical contacts 204, 205.

FIG. 6 illustrates an exemplary flexible thermoelectric fabric 300. Theflexible thermoelectric fabric 300 can include a thermoelectricapparatus as described above with respect to FIGS. 1-2 such that theapparatus forms a fabric that is capable of bending easily withoutbreaking the circuits. As such, in some aspects, the flexiblethermoelectric fabric can comprise at least one p-type layer coupled toat least one n-type layer to provide a p-n junction, and an insulatinglayer at least partially disposed between the p-type layer and then-type layer, the p-type layer comprising a plurality of carbonnanoparticles and the n-type layer comprising a plurality of n-dopedcarbon nanoparticles. In some aspects, carbon nanoparticles of thep-type layer are p-doped and carbon nanoparticles of the n-type layerare n-doped. In some aspects, a p-type layer of a flexiblethermoelectric fabric or apparatus can further comprise a polymer matrixin which the carbon nanoparticles are disposed. In some aspects, ann-type layer further comprises a polymer matrix in which the n-dopedcarbon nanoparticles are disposed. In some aspects, p-type layers andn-type layers of a flexible thermoelectric fabric or apparatus describedherein are in a stacked configuration.

In some aspects, carbon nanoparticles of a p-type layer comprisefullerenes, carbon nanotubes, or mixtures thereof. In some aspects,carbon nanotubes can comprise single-walled carbon nanotubes (SWNT),multi-walled carbon nanotubes (MWNT), as well as p-doped single-walledcarbon nanotubes, p-doped multi-walled carbon nanotubes or mixturesthereof. N-doped carbon nanoparticles can comprise fullerenes, carbonnanotubes, or mixtures thereof. In some aspects, n-doped carbonnanotubes can also comprise single-walled carbon nanotubes, multi-walledcarbon nanotubes or mixtures thereof.

In some aspects, a p-type layer and/or n-type layer can further comprisea polymeric matrix in which the carbon nanoparticles are dispersed. Anypolymeric material consistent with the objectives of the presentinvention can be used in the production of a polymeric matrix. In someaspects, a polymeric matrix comprises a fluoropolymer including, but notlimited to, polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF),polytetrafluoroethylene (PTFE), or mixtures or copolymers thereof. Insome aspects, a polymer matrix comprises polyacrylic acid (PAA),polymethacrylate (PMA), polymethylmethacrylate (PMMA) or mixtures orcopolymers thereof. In some aspects, a polymer matrix comprises apolyolefin including, but not limited to polyethylene, polypropylene,polybutylene or mixtures or copolymers thereof. A polymeric matrix canalso comprise one or more conjugated polymers and can comprise one ormore semiconducting polymers.

As a person of ordinary skill will understand, the “Seebeck coefficient”of a material is a measure of the magnitude of an induced thermoelectricvoltage in response to a temperature difference across that material. Ap-type layer, in some aspects, can have a Seebeck coefficient of atleast about 3 μV/K at a temperature of 290 K In some aspects, a p-typelayer has a Seebeck coefficient of at least about 5 μV/K at atemperature of 290 K In some aspects, a p-type layer has a Seebeckcoefficient of at least about 10 μV/K at a temperature of 290 K In someaspects, a p-type layer has a Seebeck coefficient of at least about 15μV/K or at least about 20 μV/K at a temperature of 290 K. In someaspects, a p-type layer has a Seebeck coefficient of at least about 30μV/K at a temperature of 290 K. A p-type layer, in some aspects, has aSeebeck coefficient ranging from about 3 μV/K to about 35 μV/K at atemperature of 290 K. A p-type layer, in some aspects, has a Seebeckcoefficient ranging from about 5 μV/K to about 35 μV/K at a temperatureof 290 K. In some aspects, a p-type layer has Seebeck coefficientranging from about 10 μV/K to about 30 μV/K at a temperature of 290° K.As described herein, in some aspects, the Seebeck coefficient of ap-type layer can be varied according to carbon nanoparticle identity andloading. In some aspects, for example, the Seebeck coefficient of ap-type layer is inversely proportional to the single-walled carbonnanotube loading of the p-type layer.

Similarly, an n-type layer can have a Seebeck coefficient of at leastabout −3 μV/K at a temperature of 290 K. In some aspects, an n-typelayer has a Seebeck coefficient at least about −5 μV/K at a temperatureof 290 K. In some aspects, an n-type layer has a Seebeck coefficient atleast about −10 μV/K at a temperature of 290 K. In some aspects, ann-type layer has a Seebeck coefficient of at least about −15 μV/K or atleast about −20 μV/K at a temperature of 290 K. In some aspects, ann-type layer has a Seebeck coefficient of at least about −30 μV/K at atemperature of 290 K. An n-type layer, in some aspects, has a Seebeckcoefficient ranging from about −3 μV/K to about −35 μV/K at atemperature of 290 K. In some aspects, an n-type layer has Seebeckcoefficient ranging from about −5 μV/K to about −35 μV/K at atemperature of 290 K. In some aspects, an n-type layer has Seebeckcoefficient ranging from about −10 μV/K to about −30 μV/K at atemperature of 290 K. In some aspects, the Seebeck coefficient of ann-type layer can be varied according to n-doped carbon nanoparticleidentity and loading. In some aspects, for example, the Seebeckcoefficient of an n-type layer is inversely proportional to the carbonnanoparticle loading of the n-type layer.

As described herein and in U.S. Publication No. 2013/0312806, in someaspects the flexible thermoelectric fabric can include an insulatinglayer. An insulating layer can comprise one or more polymeric materials.Any polymeric material consistent with the objectives of the presentinvention can be used in the production of an insulating layer. In someaspects, an insulating layer comprises polyacrylic acid (PAA),polymethacrylate (PMA), polvmethylmethacrylate (PMMA) or mixtures orcopolymers thereof. In some aspects, an insulating layer comprises apolyolefin including, but not limited to polyethylene, polypropylene,polybutylene or mixtures or copolymers thereof. In some aspects, aninsulating layer comprises PVDF. An insulating layer can have anydesired thickness consistent with the objectives of the presentinvention. In some aspects, an insulating layer has a thickness of atleast about 50 nm. In some aspects, an insulating layer has a thicknessranging from about 5 nm to about 50 μm. Additionally, an insulatinglayer can have any desired length consistent with the objectives of thepresent invention. In some aspects, an insulating layer has a lengthsubstantially consistent with the lengths of the p-type and n-typelayers between which the insulating layer is disposed. That is, in someaspects, an insulating layer, p-type layer, and/or n-type layer can havea length of at least about 1 ym. In some aspects, an insulating layer,p-type layer, and/or n-type layer can have a length ranging from about 1μm to about 500 mm.

As shown in FIG. 6, an exemplary mattress assembly 300 having a bodysupport 302. The body support 302 has a proximal surface 304 that cansupport a body 306. The body 306, as shown, can be a human body and thebody support 302 can be configured to support the body in a prone,supine, semi-supine, sifting, or any other position so long as the bodysupport 302 supports some portion of the body. The thermoelectricapparatus 308 can be provided intermediate the proximal surface 304 andthe body support 302 in relative close proximity to the proximal surface304.

FIG. 7 illustrates an exemplary resistive heating element 400 formed ofa flat envelope of synthetic textile material 402 containing an electricresistance wire 404 which is mostly inserted in a zigzag or meandershape but which may also have the form of a thin, flat ribbon.Alternatively, the wire 404 can be a conductive sewing thread.

FIG. 8 illustrates an exemplary heat transfer device 500. The particularheat transfer device is not intended to be limited and can includes avented bladder 502 in fluid communication with a blower assembly 504 ormay include multiple blower assemblies mounted within the foundation orproximate to the mattress assembly. An exemplary heat transfer devicesare disclosed in U.S. Pat. No. 9,326,616, entitled “Active AirflowTemperature Controlled Bedding Systems” to Dreamwell, Ltd, and U.S. Pat.No. 8,353,069 entitled Device for Heating, Cooling and EmittingFragrance into Bedding on a Bed, incorporated herein by reference intheir entireties.

The heat transfer device can include a fluid transfer device (e.g.,blower, fan, etc.), a thermoelectric device (e.g., Peltier device), aconvective heater, a heat pump, a dehumidifier and/or any other type ofconditioning device. In addition, the air supply can include one or moreinlets and outlets (not shown) through which air or other fluid canenter or exit an interior space of the air supply. Accordingly, once airor other fluid enters the interior space of the air supply (e.g.,through one or more inlets), it can be directed toward the upper layersby one or more fluid conduits and ventilated tubes. In embodiments wherea fluid module comprises (or is in fluid communication with) athermoelectric device or similar device, a waste fluid stream can begenerated. When cooled air is being provided to the bed assembly (e.g.,through one or more passages through or around the upper portion), thewaste fluid stream is generally hot relative to the main fluid stream,and vice versa. Accordingly, it may be desirable, in some arrangements,to channel such waste fluid out of the interior of the air supply. Forexample, the waste fluid can be conveyed to one or more outlets (notshown) or other openings positioned along an outer surface of the airsupply using a duct or other conduit. In arrangements, where the airsupply comprises more than one thermoelectric device, the waste fluidstreams from two or more of the thermoelectric devices may be combinedin a single waste conduit.

The control unit 108 shown on FIG. 3 is electronically connected to thesignal generating layer, e.g., heat source and can be programmed toadjust the heat as desired based on sensor data. The control unitincludes control circuitry, which can include a plug that coupled to anelectrical outlet (not shown) to receive local power, which in theUnited States could be standard 110 V, 60 Hz AC electric power suppliedthrough a power cord. It should be understood that alternate voltage andfrequency power sources may also be used depending upon where theproduct is sold and the local standards used therein. Control circuitryfurther includes power circuitry that converts the supplied AC power topower suitable for operating various circuit components of controlcircuitry.

The control unit can include a processor, a memory, and a transceiverand may communicate with the plurality of sensors wirelessly or viawired connections. Suitable sensors can include humidity sensors,temperature sensors, position sensors, and the like. In exemplaryembodiments, the control system is configured to collect the informationreceived from the one or more sensors in the memory. In one embodiment,the processor may be disposed within the active comfort controlledbedding system. In other embodiments, the processor may be locatedproximate to the active comfort controlled bedding system. The controlunit can also be programmed using algorithms effective to understand(predict) the human factor (i.e. heat output, body weight and the effectthat has on heat transfer through the compressed foam and location onthe stress-strain curve of the foam. Additionally, the control unit canbe programmed to predict a future state to adjust the amount of heatgenerated in the signal generating layer.

In exemplary embodiments, the processor may be a digital signalprocessing (DSP) circuit, a field-programmable gate array (FPGA), anapplication specific integrated circuits (ASICs) or the like. Theprocessor can be any custom made or commercially available processor, acentral processing unit (CPU), an auxiliary processor among severalprocessors, a semiconductor based microprocessor (in the form of amicrochip or chip set), a macroprocessor, or generally any device forexecuting instructions.

In exemplary embodiments, the control system is configured tocommunicate to with a user interface that a user of the active comfortcontrolled bedding system can use to modify one or more settings of thecontrol system. In one embodiment, the control system includes aBluetooth® or Wi-Fi transceiver that can be used to communicate with awireless device or wireless network. In exemplary embodiments, thecontrol system is configured to connect to a web-service over a Wi-Ficonnection and a user of the active comfort controlled bedding systems(including variable firmness control and/or variable climate control)mattress can use the web-service to modify one or more settings of thecontrol system and to view data collected by the control system that isstored in the memory. In exemplary embodiments, data collected by thecontrol system may be stored locally, on a wireless device or aweb-based Cloud service.

In exemplary embodiments, the one or more settings of the control systemmay include a desired firmness for each zone of the active comfortcontrolled bedding system that can be changed by altering the pressurewithin one or more of the air bladders. Likewise, one or more settingsof the control system may include a desired climate settingcorresponding to areas of the bedding system configured for air flow asdiscussed above, e.g., the head, lumbar, and upper leg regions. Forexample, it has been found that ambient air flow to the head regionincluding the neck area of the end user can effectively increase comfortby reducing temperature via evaporative cooling as the neck area isprone to sweating when the end user feels hot. In exemplary embodiments,the user interface may allow a user to view statistics gathered on thequality of their sleep and may provide suggested changes to variousclimate settings to help improve the quality of the user's sleep. Inexemplary embodiments, the processor may be configured to analyze thestatistics gathered on the quality of a user's sleep and to makeautomatic adjustments to the various climate settings to help improvethe quality of the user's sleep. In exemplary embodiments, the analysisof statistics can be executed on a wireless device or a web-basedservice.

For multi-user bedding systems, the pressure and/or temperature feedbackcan allow the active comfort bedding system to actively maintain adesired pressure and/or comfortable climate with respect to eachoccupant. Since no two occupants are identical, the system can beconfigured to sense the pressure and/or the surface temperature and/orrelative humidity and responds accordingly rather than a one size fitsall approach.

To facilitate operation of the bedding systems described above, thebedding systems can further include one or more sensors to automaticallyadjust to body position, which can be used to fall asleep faster andprovide uninterrupted sleep. The types of sensors are not intended to belimited and may include pressure sensors, load sensors, force sensors,temperatures sensors, humidity sensors, motion sensors, vibrationalpiezoelectric sensors and the like.

In one or more embodiments, a process for changing a firmness propertyof a foam layer in a mattress assembly can include providing themattress assembly with at least one viscoelastic foam layer having afirst glass transition temperature greater than 60° F. at 0% humidity,and a second glass transition temperature less than the first glasstransition temperature at a % humidity greater than 0. The at least oneviscoelastic foam layer can be heated and/or the ambient humidityconditions about the at least one viscoelastic foam layer can be changedto alter the firmness property. For example, the at least oneviscoelastic foam layer can be heated above the second glass transitiontemperature and/or the ambient humidity conditions can be increased bymixing air about the mattress assembly with moisture and exposing the atleast one viscoelastic foam layer with the air and/or the ambienthumidity conditions can be decreased by removing moisture from air andexposing the at least one viscoelastic foam layer with the air. The termambient humidity conditions generally refers to an environment in whichthe mattress assembly is disposed.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to make and use the invention. The patentable scope of the inventionis defined by the claims, and may include other examples that occur tothose skilled in the art. Such other examples are intended to be withinthe scope of the claims if they have structural elements that do notdiffer from the literal language of the claims, or if they includeequivalent structural elements with insubstantial differences from theliteral languages of the claims.

What is claimed is:
 1. An active comfort controlled bedding systemcomprising: at least one viscoelastic foam layer having a glasstransition temperature greater than 60° F. at 0% humidity, wherein theactive comfort controlled bedding system is in an environment havinggreater than 0% humidity; a signal generating layer underlying the atleast one viscoelastic foam, the signal generating layer comprising athermoelectric fabric, a heat transfer device, or a resistive heatingelement; and a control unit in electrical communication with the signalgenerating layer configured to generate heat and alter a firmnessproperty of the at least one viscoelastic foam layer, wherein the amountof heat is based on a decrease of the glass transition temperature as afunction of the percentage of humidity in the environment.
 2. The activecomfort controlled bedding system of claim 1 further comprising anencapsulated paraffin wax stratified in the at least one viscoelasticfoam layer.
 3. The active comfort controlled bedding system of claim 1,wherein the at least one viscoelastic foam layer having a glasstransition temperature greater than 80° F. at 0% humidity.
 4. The activecomfort controlled bedding system of claim 1, wherein the at least oneviscoelastic foam layer having a glass transition temperature greaterthan 90° F. at 0% humidity.
 5. The active comfort controlled beddingsystem of claim 1 further comprising at least one sensor for determiningbody position on the bedding system.
 6. The active comfort controlledbedding system of claim 1, wherein the signal generating layer comprisesmultiple zones to alter the firmness property specific to each of themultiple zones.
 7. The active comfort bedding system of claim 1, whereinthe control unit further comprises electrical communication with ahumidity sensor and a heat sensor.
 8. An active comfort controlledbedding system, comprising: at least one foam layer comprising a phasechange material stratified in a foam structure of the at least one foamlayer; a signal generating layer underlying the at least one foam layer,the signal generating layer comprising a thermoelectric fabric, a heattransfer device, or a resistive heating element; and a control unit inelectrical communication with the signal generating layer effective toheat the phase change material above a melting temperature thereof andalter a firmness property of the at least one foam layer.
 9. The activecomfort controlled bedding system of claim 8, wherein the foam layercomprises a latex foam, a polyurethane foam, or a viscoelastic foam. 10.The active comfort controlled bedding system of claim 9, wherein the atleast one viscoelastic foam layer has a glass transition temperaturegreater than 60° F. at 0% humidity, and the signal generating layer isconfigured to generate heat and alter firmness property of the at leastone viscoelastic foam layer, wherein the amount of heat is based on adecrease of the glass transition temperature as a function of thepercentage of humidity in an environment of the active comfortcontrolled bedding system.
 11. The active comfort controlled beddingsystem of claim 9, wherein the at least one viscoelastic foam layer hasa glass transition temperature greater than 80° F. at 0% humidity. 12.The active comfort controlled bedding system of claim 9, wherein the atleast one viscoelastic foam layer has a glass transition temperaturegreater than 90° F. at 0% humidity.
 13. A process for changing afirmness property of a foam layer in a mattress assembly, the processcomprising: providing the mattress assembly with at least one foam layercomprising a phase change material stratified in a foam structure of theat least one foam layer; and heating the at least one foam layer to atemperature greater than a melt temperature of the phase change materialto soften the at least one foam layer.
 14. The process of claim 13,wherein heating the at least one foam layer comprises generating heatfrom a thermoelectric fabric underlying the at least one foam layer. 15.The process of claim 13, wherein heating the at least one foam layercomprises generating heat from a heat transfer device underlying the atleast one foam layer.
 16. The process of claim 13, wherein heating theat least one foam layer comprises generating heat from a layercomprising resistive heating elements underlying the at least one foamlayer.
 17. The process of claim 13, wherein the at least one foam layercomprises a viscoelastic foam layer having a first glass transitiontemperature greater than 60° F. at 0% humidity, and a second glasstransition temperature less than the first glass transition temperatureat a % humidity greater than 0, and wherein heating the viscoelasticfoam layer comprises heating above the second glass transitiontemperature to alter the firmness property.
 18. A process for changing afirmness property of a viscoelastic foam layer in a mattress assembly,the process comprising: providing the mattress assembly with at leastone viscoelastic foam layer having a first glass transition temperaturegreater than 60° F. at 0% humidity, and a second glass transitiontemperature less than the first glass transition temperature at a %humidity greater than 0; and heating the at least one viscoelastic foamlayer comprises heating above the second glass transition temperature toalter the firmness property.
 19. The process of claim 18 furthercomprising a phase change material stratified in a foam structure of theat least one viscoelastic foam layer.
 20. The process of claim 18,wherein heating the at least one viscoelastic foam layer comprisesgenerating heat from a thermoelectric fabric underlying the at least oneviscoelastic foam layer.
 21. The process of claim 18, wherein heatingthe at least one viscoelastic foam layer comprises generating heat froma heat transfer device underlying the at least one viscoelastic foamlayer.
 22. The process of claim 18, wherein heating the at least oneviscoelastic foam layer comprises generating heat from a layercomprising resistive heating elements underlying the at least oneviscoelastic foam layer.
 23. A process for changing a firmness propertyof a foam layer in a mattress assembly, the process comprising:providing the mattress assembly with at least one viscoelastic foamlayer having a first glass transition temperature greater than 60° F. at0% humidity, and a second glass transition temperature less than thefirst glass transition temperature at a % humidity greater than 0, andheating the at least one viscoelastic foam layer and/or changing ambienthumidity conditions about the at least one viscoelastic foam layer toalter the firmness property.
 24. The process of claim 23, whereinchanging ambient humidity conditions about the viscoelastic layercomprises increasing the ambient humidity conditions by mixing air withmoisture and exposing the at least one viscoelastic foam layer with theair.
 25. The process of claim 23, wherein changing ambient humidityconditions about the viscoelastic layer comprises decreasing the ambienthumidity conditions by removing moisture from air and exposing the atleast one viscoelastic foam layer with the air.
 26. The process of claim23, wherein the ambient humidity condition has a different humiditylevel relative to a sleeping surface of mattress assembly.
 27. Theprocess of claim 23, wherein heating comprises heating the at least oneviscoelastic foam layer above the second glass transition temperature